Up, down, more, less, longer, shorter?

I like my VW Golf estate. It’s a great family car / dad car. Practical and kind of cool looking (to other dad’s at least). But specifically I’m liking the internal switches and buttons and things. Except for the windscreen wiper one. This one:

In particular, that little toggle like switch on top, with what looks like a volume or signal strength icon underneath. I think it controls the duration of the slowest windscreen wiper setting (when the lever is pushed up one click), but I can never quite figure out, or remember, if the the low end of the icon (switch to the left) means slower wiping, or smaller gaps between wiping (which would mean faster wiping).

Maybe it’s just me and a now inbuilt confusion of which way is which. Like people who struggle to remember which way round their mnemonics go, like the one with holding your hand up, fingers together with thumbs out, so as to create an L shape to tell you which hand is left. Except you need to remember which way round your hands go, otherwise your right hand makes the L.